Rectifying alternating current.



E. WEINTRAUB.

' RECTIFYING ALTRNATING CURRENT.

' APPucATloN-meo'mn. 2a, |903. 1,134,786. Patented Apr. 6, 1915.

2 SHEETS-SHEET 1.

.IQ/MM,

' E. WEINIHAUB.

v RECTIFYING ALTERNATING CURRENT. Y APPLlcmon msn MAR. 23. 1903.1,134,786. Patented Apn, 1915.

2 SHEETS-SHEET 2.

Witnesses'. Inventor:

/EWg/f vlEzevchiel Weintrja'uby' fri/dy.

nzncHIEL WEINTBAUB, or soHENncTADY, NEW YORK,

AssIcfNon'.M To yGENERAL ELECTRIG COMPANY, A CQRPORATION OFNEW YORK.

'n.Eo'rIrYING ALTERNATING curateur.l

Sp-ecicationlof Letters Patent.`

Patented Apr. .6, 1915.

Application led March 23, 1903. ySeriallo. 149,084.

To all 'whom it may concern -'Be it' known that I, llznorminl WEINTRAB,

a subject' ofthe Czar of Russia, residing at Schenectady, county ofSchenectady, 'State of Newv York, have invented certain new and usefulImprovements Rectifying Alternating Current, of which thev following isa specification.

l My invention relates tothe rectification of alternating current andcomprises various -improvements in theconstruction and arrangement ofthe rectifying apparatus] and In the circuits and systems ofdistribution" apparatus may 'be employed. f f

in connection with lwhich'the In rectifying alternating current Imakeuse of a property, discovered by me, that'- a i to this unsymmetricalconducting'character vapor, such for example as the vapor of' mercury,produced `in an exhausted recep# 20 tacle by means of electrical energypassed into said receptaclethrough electrodes suit-, ably locatedtherein, isa conductor for current flowing in one .dire ction --throughthe vapor and a non-conductor for current tending to'iow inf theopposite direction. Due

of the medium an alternating electro-motive force, when impressed uponsuch electrodes,- causes a unidirectional current to-iiow be-. tween theelectrodes. As I have set forth in my copending application, Serial ,No

149,083, led. concurrently# Aherewith,` the luminous character of thevapor renders my. inventionalso useful in Vthe production of light, inwhich case, of course, the size andshape of the exhausted receptacle maybe chosen accordingly. The various features of novelt which characterizemyv invention I-have pointed out with particularity .intheappended'claims. The invention4 itself, however, willbe Vbest-understood by reference tothe following de- .scription taken inconnection with the accompanying drawings inv which- Figures l, 2, 3,and 4 represent the vapplication-.0f my invention to the rectificationof Si'gmle phase alternating current. wh'le e j Figs. `5 and -6represent modifications of invention shown in Figi, and Fig. 7represents a modificationof the inventioshown in Fig. 2. i

In Iig. l which represents one of the simpler forms of a rectify'ingapparatus,

madey in accordance with my invention, I em- -cylin'de'r -l provided atthe' leading-in conductor 64 ploy afreceptacle liof any suitable formand made of a material suchas glass, or fused quartz or silica.Other-materialsmay however1 be chosen, such for exampleas metal, inwhich case the'receptacle should be coated either. inside or outside -orboth witha hard glaze lmperviousxtoair. -If metal yalone were used,the-extremely high; vacuum which it `1s necessary :to maintainin'thereceptacle f Y in order to slow deterioration through leakage of airthrough the pores ofthe metal. This ,leak-- age Ahas only to; be vveryslight 'in' order'to impai-r Athe vacuum. .I findfit 'convenient'however inorder to observe the working of the apparatus tomakeareceptacle of someA light-con noting-.material such as heretoforem`entior`1ecl. V The shapeof the envelop may hewidely variedwithoutdeparting from Kto obtain the best results is liable myinvention. In Fig. 1, the receptacleor envelopisfrepresented asasomewhat squatty.'

bottom with "a series of cups arrangedto contain bodies of' mercury 2,3, 4.wh1 ch operateas electrodes.

Mounted inthe top of the rec'zeptaclek is a cooperating-cleetrode 5 ofsome suitable material such as iron, Vartificial graphite or the like.This .electrode'is supported vfrom a throughout its length by aprotecting sleeve' 7 'ofnon-conductin'g material; vLeadingin wires 8;y 9and 10 are also provided for making electrical connections-with therespective mer-y cury electrodes 2,3, and 4. The alternating currentvsuppl y mains, from which the current supplied t o the vapor rectifieror converter of these mains isv connected to the electrode which isprotected A 'isderived, are indicated at 11 and 12. One

2 and the other toelectrode 4 and through thetranslating devices totheelectrode 5. A

switch l13 serves however to interrupt the connection Withtlie'electrode4 for a purpose v hereinafter to vbe mentioned. lThe middle mercuryelectrode 3 constitutes one o f the nected-A through an inductance coilor reactance -14 with thefsupplfy'mainll. In the circuit between lthemain 12 and the main electrode are connected the translatingde.

las i vlces or apparatus to which it is desired to supplytheunidirectional or rectified current derived thro-ugh theinstrumentality of the'. 4 apparatus described. The current-consumin gor translating devicesmay of coursebe 'main electrodes-of the `rectifierand i's conas the agitation thus caused subsides,

l between the cups asat 18 and 19 and thus of any desired charactereither all alike or of different varieties as desired. As illustrativeof such current-consuming devices I,

have indicated diagrammatically a storage battery at 15, lamps at 16,and a motor at 17.

In starting up the apparatus, the circuit of the supply mains that theelectrodes2 and 4 are in electrical communication with the source. Theswitch y13 is also closed. The mercury in the three interrupts thecontact momentarily formed and so produces electrical arcs across thetwo bridges or walls at 18 and 19. Thethen be opened, `which thereswitch13 may upon has the effect of causing the arc ,be-

tween the electrodes 4 and 3 to be trans,-`T

ferred to the main body of the receptacle i1 and, to tliereaftertakeplace between tl'ie upper electrode 5 land the electrode After theapparatus has been thus started, and whether the current from the mainslflows vinto the electrode 4 with the switch 13` closed, or into theelectrode 5 with the said f switchA opened, a unidirectionall current"flows inthe rectifier. f This unidirectional current' is utilized inthe consumptioncircuit, 'the character of which has already beendescribed.

In explaining the action of the apparatus,

let it be supposed that with `the switch 13' closed a positive wave, or,perhaps more coi'- rectly speaking, halfv period of current, flows fromthe electrode 4 to the electrode .3 and thence through the inductancecoil 14 and back to the source. AAs soon as the current in the mainstends to reverse in; direction, the current acrossthe electrodes 4 and 3ceases. 'Before this happens lthe electromagnetic energy stored up inthe inductance coil 14 through the passage ,therethrough of the previoushalf wave of current discharges through the circuit including theelectrodes A2 and 3. This How of current, according to g well knownlaws, is in the same direction as thel current which, so tospeak,produced the electromagnetic charge of the inductance coil. Acur'rentdischarge or arc therefore takes place -from the electrode 2. to themiddle electrode 3. During the vtime that no current flows from thesupply circuit, the inductance coil 14 supplies current tothe rectier..The arcs occurring in the rectifier which separate during overlappingtime intervals -serve das starting.. means'for eachother and `so keepthe rectifier in operation.

. The translating devices may be connected in series with the.-induc'tanceI coil, as at,105,

in Fig. 5, and then receive current which in- 11 and 12 is closedso\"/'stead of being in the formllof a series4 of intermittentpulsations is nearlyv continuous, a result which is accomplished by thestoring and restoring of energy in the inductance coil alternately withthe flow and periods of cessation-of flow of current in the supply'circuit; The translating-devices may also.

be placed `in series w' h the electrode 4 'in Fig. 1', inwhich case theyreceive a'pulsating or intermittent unidirectional current. Thisarrangementv isshown in Fig. 6 in which the translating devices areindicated at 106.

TheI rectifier may operate with the arcs or current iiow taking placeentirely in the bottom of the receptacle 1 but, as has been indicated,the current iow or arc between the main body of the receptacle 1 byyopening the switch 13. This kmay bel of advantage by reducingthe amountof mercury vapor in the -tube and thus making the arc more stable. Thetranslating-devices may the electrodes 3 and 4 may be transferred to lthen be placedin circuit with the main elec- "trodefs as indicated.

In the arangement shown in Fig. 1, only waves of a given polarityderived from the source of supply are utilized, waves of the op- 'positepolarity being suppressed. In order to utilize both waves 4of current,the arrangement shown'in Fig. .2 may be used. In this case thereceptacle 2O is substantially the same as the receptacle' 1 in Fig.1,except however `that it is provided with two upper electrodes 21 and22instead of a single electrode as 5 ,in Fig. `1. Tw'o inductance coils 23and 24,

connected in series with eachother, arel employed instead of one.` Acircuitv containing the translating devices indicated for example at 25is connected between the junction between'theinductance coils 23 and 24and the lower or cooperating main electrode 26. The two electrodes 27-and 28 are con! nected respectively through switches 29 and y30 to thesupply mainsl and 32. In starting up the rectifier substantially thesame procedure lis gone. through as in the case of the rectifierdescribed -in Fig. 1. Displacement of the mercury may be performed ineither case by manual means as described'or by automatic means such forexamplea shown in Fig. 7 in which a solenoid 10.7 external to theerctifler operates upon a mer.-

cury-displacing float 108 to raise dr lower Y the level of the mercury109, thus joining or at will the bodies of mercury in separating b tt oy om` o the mercury-retaining cups at the the receptacle. When the twoarcs havc been formed at the bottom of the receptacle 20, Fig. 2, thecurrent flow may be transcurrent iowthrough the rectifieruntil anunseres ferredyto'the u perpmain. electrodesv 21 .and 22y by-opening t erespective switches 29 and'A l 30.- The operationis in acertain senseacharge of electromagnetic-energy. -As soonv as the half wave of current,commences to decrease in Value, the inductance coil 24 commences todischarge. and prolongs--this flow of current until acurrent-waveof-opposite polarity from the source-ows 'from the main l22through the electrode--21,then

through the retier and, after passing Y 4' through the translatingdevices,` returns through the other or supplemental inductance `coil 23.Thisy inductance coil is therefore in its turn charged so that upon achange of polarity of thesupply mains it prolongs the arc agaip passes,vas before, between-electrodes 22 and 26. L v

In both of the arrangements shown `in Figs. .1 and 2 the continuousoperationof the apparatusis dependent upon -the .fact that before onearc or `discharge ceases to flow, another one tends to come into)existence. The presence of an arc inv the envelop at the-time there isa tendency ,for another arc to form, enables the latterarc to come intoexistence by supplying mercur ions which ,create a conducting medium orthe latter arc. The separate arcs' therefore ym11- tually enable eachother to start and are dependent upon eachother 4for `their existence.

If the arcs were,to`bereducedin number to one, that one also would ceasetoow since,

' las lwillbe understood from what has 4already been said,`the 'currentwould stop iiowing for one half wave'and-when it should'start vapor.'

again there would be no'vmercury ions or conducting medium in theenvelop thus pre-v ventin a continuance of the ow until again starte bythe initiahproductionof" ionized .In the I. arrangement in -Fig. 2 vthesymmetrical utilization, of the .energy -.`de. rived from thealternating current-sourceis' s uch that the resultingjcurrentiflowinfthe circuit carrying therectifiedzlcurrent isal-v most absolutelysteady. The flow gif-energy in the .translating devices ,istherefor'esubfactor o the current supplied is -found to be practically unity, thepulsating tloW')- of power inthe supply circuit has ybeen `changed.

1 .into a constant ow of ower in .thecons'llmpx tion circuit through t@energy storing Aand restoring action of theinductancej-coils-23 and 24.

Instead. of using electrodes' 'auch .as

while a 21;and22- in the upper part of thejrectier and transferringy thearcs thereto 1 from. the

#starting electrodes, I- may confine vthe field of lactivity in therectifier to the space immediately about thelowerelectrodes.- An

' arrangement for edecting this purpose .is l shown in Fig. 3 which issubstantially the same as Fig.' 2 except that the upper electrodes-havebeen omitted together with the' leads extending thereto. The supplymains aregsh'own at V35 and 36. and across thesemainsf are 4connectedthe inductance 'coils 37 and38. #The receptacle 39, of substantially thesame formr as that shown in the previously described figures, isprovidedyat its lower portion with the three' mercury electrodes 40, 4land The consumption circuit, Vindicated generall at`43, has oneleadlconnected to the mi dle electrode `411 andvthe otherto ,thejunction between:the

two inductance coils. 4The starting and operation ofzthe arrangement issubstantially the-same as-that shown .in1Fig. 2. In this instancehowever the upper portion of the chamber 39 is utilized as a condensingchamber for cooling 'the mercury Vapor and thus preventing the voltageof the rectifier from becoming too high andthus rendering'its operationunstable. 4To assist in securing stability ofoperation, Il connectv incircuit with'the mains leading tolthe rectifier aresistancesuch asindicated at 44 in Fig. 3.

Similar steadying resistances .are usedalso 1n' thearrangementsydescribed 1n connection with Figs.- l andl 2 and-also inconnection with the arrangements hereinafter to be dec scribed. Inasmuchasthis feature is coma mon to all' of the rectifying devices, I con-Sider it unnecessary to refer againto the use of the resistances.specifically. Inasmuch i however as anon-lnductive resistance consumesenergy, I may replace it b an inducti-v'e resistance, thus attaining stailiy without undueexpenditure of energy. chan inductive resistance Ihave indicated at 45 in-Fig'.v ,4, I'havev madeclaims to this-feature ofmy linvention in my'copending application, Serial No.267,720, led JuneB0,

' 1905, which application is a division ofthe present application.- l.Fig..4,-which1have usedzto illustratethe application of an inductivesteadying means,

represents a rectier which is substantially' thev same in principle asthat show in-Fig. 3 except that the electrodes'40 and 42, inas---m'uch-as they operate as anodes and are stantiall constant. linasmuchas-:theV- I'iower4 therefore not requiredto be vaporized .tir

*sustain-the flow ofcurrent, are replaced by electrodes ofnon-vaporizable material. The- .receptac1e-in-this case a assumes a,substanf tially lcylindrical aspect as shown at 46. In t e lowerportion ofthe receptacle is. a reatively large body of mercury 47. whichoperates as the common cathode. .The two corresponding anodes :48.andati vof iron,

graphite or the like, are supported from the top3of the receptacle asindicated, and the supporting conductors are surrounded by protectingtubes 50 and 51 of insulating material. The inductance coils orenergystoring devices are indicated at 52 and 53 and are connected inseries with eachother across thesupply mains 54 and 55. The anodes 48and 49 are connected respectively to the supply mains and the cathode 47yto the junction between theinductance coils as shown. Suitableleadingin wires are employed for the purpose of conveying currentthrough the walls of the envelop or receptacle. To start the rectiiier,the evel of the mercury 47 israised so as to touch, and then separatefrom, the aodes48 and 49 thus starting the arcs, thev operation of whichhas already been described in some detail. The contact between themercury and the upper electrode may be eifected by shaking thereceptacle or by some electrical or otherwise actuated mechanism forraising `or lowering the level of the mercury, the precise details ofthe arrangements Vused being susceptible of considerable variation. Inthe preceding description I have referred chieiy tothe use of inductancecoils as the agency for storing and restoring energyl but it is to beunderstood that'I may employ in place thereof any other suitable energy-storing or reactance -possessing dey vices. In other words, myinvention when considered in its broader aspect is not to be limited toany particular form of energystoring device. Moreover, although I haveindicatedv in a general way the mannerpin which I at present believe myinvention to operate, I do not advance these. theories as absolutevfacts, or 'hold myself responsible for their accuracy.

What I claim as new and desire to secure by Letters Patent of the UnitedStates, is,

1. The combination of anexhausted envelop, velectrodes therefor, one atleast of which is of vaporizable material, a source of 4single-phasecurrent connected -to saidV electrodes, means for causingar continuoussuccession of current waves to flow from sald source through saldenvelop, and a oo nsumption circuit fed by the current passing\ throughsaid envelop. Y

2.' The combination of an exhausted rei vceptacle, a pluralit ofelectrodes ofmonable electrode, 'means for impressing electro-motiveforces of opposite polaritis upon said non-vaporizable electrodes, areturn circuitfleading fromthe vaporizable electrode, A v

acurrent consuming deviceor current-consuming devices in said circuit,andmeans .-for causing alternate pulsations of current to take placebetween said non-vaporizable electrodes and the vaporizable electrode.

3. The combination of an exhausted envelop,` a sourcel ofsingle-phase'alternating current, non-identical paths through saidenvelop for current from said. source, and a current-consuming device ordevices trav- 'ersedby the current passing through said 4l Thecombination of an exhausted envelop or receptacle, a .source ofsingle-phase alternating current, separate paths through said'receptaclefor current from said source,

vmeans for causing current of the, same polarity to flow alternately insaidpaths, and

current-consuming means external to said receptacle for utilizing theenergy ofthe current'lowing through said receptacle.

5. The combination of an exhausted envelop, electrodes therefor, a,source of single-v v connected acrossV said source for utilizing ,onepolarity Wave of current from said Q source, and supplemental means forcausing. J

energy due to waves ofthe other polarity to pass through saidvrectifier'. 7. The method which consists in causing unidirectionalWaves` from an alternating current source to iow throughja vaporconducting medium which is non-conducting for waves of oppositepolarity, causing thev waves thus flowing to traverse an energystoringdevice, causing current discharges from said energy storing device to,bridge over the zero points in said waves so that the resulting currentis cintinuous, and p assing the resulting current toa consumptioncircult.

'8. The combination of a source-ff singlephase alternating current, acurrent consummg' means, and vapor rectiying means for rectifying both`polarlty waves ofthe alternatmg current and sending the rectifiedcurrent to said current consuming means.

9. In a current rectifying device, a negative electrode, a plurallty ofpositive elecng mains connected to said positive electrode's, aconsumption circuit extending:

trodes, a source of alternating current havfrom said negative electrode,and an inductance' device in series in said circuit.

10. A current rectlfying de-v1ce,'co prising a negative electrode, aplurality o posi-4 tive electrodes, a consumptionv circuit extendingfrom the negative electrode, and an linductance device in circuit tiveelectrode. v 11.-' A current, rectifying device,- compriswith saidnegaing a negative electrode, a plurality of posi,-`

tive electrodes, a consumption lcircuit: ex-

tending from the negative electrode, and an energy storing"and-restoring device in circuit with said negativeelectrode.

12. The combination of a single phase 'vapor rectifier including as aart thereof areactance in 'series with the circuit of the rectifiedcurrent, and `current-consuming means in series with said reactance.

13. The combinationof a vapor rectifier including as a part thereof aninductance in the ycircuit of the, rectiied current, andcurrent-consuming means 'in' series with said inductance.

14. The combination of an' exhausted envelop, a source of single-phasealternating current, and means for causingl current derived from saidsource to'iow continuously in said envelop.

15. The combina-tion of a source of single- 'phase alternating current,an exhausted envelop, electrodes therefor, and means operated by currentfromsaid source for causingv a unidirectional iiow of current from saidsource through said envelop.

16. The combination of a source of al-ternating current." an envelopadapted .to con? tain a vapor conducting-medium, and means lfor derivingan alternating current from 'said source and for. transmitting theenergy of said current through said conducting medium.

17l The combination of an envelop, a

source of' alternating current, meansl for generating in 'said envelop aplurality of overlapping Vsupplemental or starting arcs by energyderived from said source, and means dependent upon the presence of said'starting a-rcs for initiating the vmain current flow or arc in saidenvelop.

18. `'1`he`combinationcf an exhausted en velop,` a plurality of lanodes,'a cathode, re-v actances connected! respectively between the with saidsource for .producing cathode andthe anodes, and a source of'alternating current connected to said anodes. 19. The combination of anexhausted envelop, a plurality of l'anodes,- ay cathode, energy storingand restoring devices connected respectively Abetween the cathode andthe anodes, and 'a vsource of" alternating Y'c'urrent connected to saidanodes.

20. The combination of an exhausted en' velop, a cathode, anodes locatedadjacent to said cathode, a plurality of anodes locatedat a distancefrom said cathode,'a source of alternating current, means associatedoverlapping arcs between said cathode an its adjacent anodes, and meansvfor .transferring the seat of operation of said arcs to the space beftween said cathodeand the remaining anodes.

21. The. combination of an exhausted envelop adapted to contaln avapor-conducting-medium, main electrodes therefor, supalternatingcurrent, means associated with plemental electrodes therefor, 'a sourceof said-source -forr roducing' overlapping arcs in said envelop rom.said supplementalelectrodes, and means fortransferring the arcs to themain electrodes.

29.. The ycombination of an exhausted 'envelop, a' source of singlephasealternating current, vand means for supplying current from saidsource t0 said envelop so that the- A. yThe combination of an envelopadapted to contain a vapor-conducting-medium,

a plurality of electrodes,- one at Aleast of l which is'of vaporizablematerial, a source of alternating current,-inductance coils c onnected1n series with each 4other across mains leading from said source, meansfor conveying current between a vaporizable electrode and a' point inthe circuit between said reactance coils, and connectionsfrom saidsourceto aplurality o'f other electrodes.-

l25. The combinationof anenvelop or receptacle, electrodes therefor, oneat least of` vwhich is of vaporizablel material, a source ofalternatlng-current, and means for generating or' produclng 1n saidreceptacle arcs other indirectly.

26. lThe method of causing. a substantially .continuous ow'of powerthrough a vapor conducting-medium, which vconsists in -de rlvlngalternatin'gcurrent from a slnglephase source, *causingcurrent fromsaid' vor electric discharges, one receiving its 'energy directly from?said source, and the 10o source to flow through said medium. and

Storingand re-storing energy derived Afrom` saidsource so as ,to producea substantially continuous vexpenditure of energy v1n said medium asdistinguished from a pulsating flow of power derived from said source.

. 2 7. The method which/consists in causing 'unidirectional waves froman alternating4 current source, to'owthrough a' given path n a vaporconducting-medium which given path is non-conducting site polarity,causing t to traverse an energy-storing device, and causing currentdischarges from said energy for waves of oppoe waves thus flowing.

storing device to flow in said medium vso as to bridge over to a greateror less extent `,the intervals during which no .current from saidsourceflows over said path.

28. The combination of a source of alternatlng current, a vaporconducting-medium traversed by current directly from said source, and anenergy storing device for rece1v1ng ener -wh11ecurr ent 1s tlowm fromsaid source rough sald medlum and or d e- 1livering the energy thusstored to` a circuit including said medium during such intervals as thevcurrent from said source is not flowing directly to a circuit includingsaid medium.

29. Asa means for maintaining an arc between substances which would not.ordinar- -ily arc withl alternating current, the combination withelectrodes of suchsubstance or substances, of energy-storing means forstor-j ing the energy of the alternating current when the current is notina proper direction to pass through the arc and then re-storing it tothe arc in the proper direction. p

- 30. The combination with a source of single phase alternating current,electrodes connected to said source of such nature and so related toeach' other as to prohibit an alternating flow of current in the form ofan arc between said electrodes, and means for deriving an alternatingcurrent from said source and causingjsaid alternating current tov'lowbetween said electrodes in the form of director unidirectional currentarcs.

31. The combination of a source of alternating electro-motive force, amedium initially non-conducting for current from said source, electrodescommunicating with said` medium and connected to said source, and meansfor Vcausing current waves of both polarities to How from' said sourcethrough said-medium. l

32. The combination of an exhausted envelop, electrodes therefor, one atleast of which is ofv vaporizable material, a source of single-phasecurrent connected to said elecbtrodes, and means for causing acontinuous succession of current waves to iow fromV said source throughsaid envelop.

-33. The combination of a source of alternating current, a, vaporconducting medium having a cathode anda plurality of andes connected tosaid source, and a device having reactance interposed in a lead betweensaid source and v:one of said anodes.

34. The combinationof a source of alternating current, a vaporconducting medium having a cathode and a plurality of anodes connectedto said source, anda steadying de-v vice consisting of a reactancetraversed-by said anodes.

35. The combination of a source of alternating current, a vaporconducting mediuml in circuit with said source, and means pos- .50lcurrent passing from said source to one of sessing reactance`interposedy between said source and said vmedium andoperating to Aprevent cessation of current in said medium at times when no currentflows from said source.

36. The combination of`a source of alternating current, a vaporconducting medium in circuit with said source, and means possessingreactance traversed by current passing lin said medium and operating toprevent cessation of current inv said mediumat times when nol currentiiows from said source.

37 The method of regulating an electric circuit in which -a vaporconverter of the character described is interposed, which consists instoring .energy by means cfa Dsuitpreventing by thesame means'a fall ofpo tential below the operative limit of the converter. f'

In witness whereof, I have hereunto set my hand this 20th day of March,1903.

EZECHIEL WEINTRAUB.

Witnesses: 'f BENJAMIN B. HULL, HELEN ORFORD.

